In laptop computers and other electronics, hot components near the inner case wall often create external hotspots that can be uncomfortable or dangerous to the user. In other words, when an electrical component is being used, the electrical component may generate heat. This electrical component may transfer heat to the enclosure of the device, thereby to the user, which essentially creates a hotspot on the enclosure that may be uncomfortable or dangerous to the user especially in the case of a metal enclosure.
The International Electrotechnical Commission (IEC) provides a set of standards for electrical devices, which includes a maximum temperature limit for areas on the device itself. Typically, most electronic manufacturers adhere to this requirement by limiting the temperature below the maximum temperature provided by the IEC. One particular example of an IEC standard indicates that if the device has a metal surface (e.g., easily conducts heat) the metal surface has to be held at a lower temperature than a plastic surface. For example, with heated metal surfaces, the heat can quickly be transferred to the user touching the hot metal surface; therefore, the metal surface can feel relatively hot even at a relatively low temperature. However, metal surfaces for electrical devices are typically used because they can quickly transfer heat from the hot electrical component, thereby keeping the hot electrical component cooler. As such, in some situations, a hotspot on the metal enclosure may occur over the hot electrical component. Further, in the event that an electrical component (e.g., CPU) is processing video graphics, the metal case enclosure may be very hot in the area of the CPU.
Generally, in order to avoid a hot spot on the metal case enclosure, a system designer may create an air gap between the hot component and the enclosure. The size of the air gap may be relatively proportional to the usefulness of the insulation, e.g., the larger the air gap between the hot component and the enclosure, the better the insulation. As such, the size of the air gap may be considered a critical item for determining the overall thickness of the device. With that said, in the area of consumer electronics, smaller electronic devices may be more marketable. In contrast, bulkier consumer electronics may have a perception of being lower quality. Therefore, there may be an incentive to design an electronic device as small as possible, which greatly affects the air gap, thereby affecting the heat transferred to the user.